Sahih Bukhari | Volume 7 | Hadith Number 46

The Prophet forbade that a woman should be married to a man along with her paternal aunt or with her maternal aunt (at the same time). Az-Zuhri (the sub-narrator) said: There is a similar order for the paternal aunt of the father of one's wife, for 'Ursa told me that 'Aisha said, "What is unlawful because of blood relations, is also unlawful because of the corresponding foster suckling relations."